Grammar: base 2 ending and continuity.

Thinking of 「修羅の花」 again and trying to figure out 身を委ね. The verb is 委ねる, to entrust to or give up to.

恨みの川に身を委ね（て）
女はとうに捨てました
Casting herself into a river of vengeance/enmity/resentment,
the woman is already left behind / abandoned / forgotten.

This makes sense to me as a -て form, because then the verbs 委ねる and 捨てる would sequence:

恨みの川に 身を委ねて、
女は
とうに 捨てました。

I'm thinking the position of 女は can't be just poetic (as is 行く女 earlier in the song); it feels like we're already talking about someone, the someone with the parasol and the geta, and now we're emphasizing the trait of womanliness. She has given herself up to a river of vengeance, and her woman-ness is already / long ago forgotten.

I guess 委ね would correspond to ichidan base 2, no? -- like 食べ. Lampkin先生 discusses bases.... Aha! It must be what Lampkin calls a continuation form, maybe less discrete in sequence than a -て form would be. So, she casts herself into the river of vengeance, and her womanliness is already left behind. The sequence still feels a little weird with とうに, but it's starting to make more sense. I didn't know about that use of base 2.